Integrated circuit packages which comprise more than a single integrated circuit die are known. For example, such integrated circuit packages may comprise two dies each comprising one or more integrated circuits, and the dies are interconnected internally in the package. For example, one die may comprise a digital signal processing integrated circuit, while the other die may comprise an analogue integrated circuit such as a digital-to-analogue converting circuit. Ideally, the number of pin connectors or other such external connectors or terminals of the package should be minimised. Thus, in general, such packages are provided with an appropriate number of input pin connectors for applying digital data to the digital signal processing circuit die, and one or more output pin connectors are provided for outputting analogue signals from the analogue circuit die. In general, the dies are provided with input and output bond pads, the number of input pin connectors to the digital signal processing circuit die corresponding to the number of input bond pads, and the input bond pads are coupled by bond wires to the corresponding input pin connectors. The number of output pin connectors from the analogue circuit die corresponding to the number of output bond pads, and the output bond pads are coupled by bond wires to the corresponding output pin connectors. Output bond pads from the digital signal processing circuit die are coupled to corresponding input bond pads of the analogue circuit die by bond wires, which are located internally within the package.
While the pin count is minimised in such two-die integrated circuit packages, unfortunately, testing of such dies can be problematical, due to the lack of externally accessible input and output pin connectors to the two dies, and in particular, due to the lack of externally accessible pin connectors coupled to output bond pads from the digital signal processing circuit die, and the lack of externally accessible pin connectors coupled to input bond pads to the analogue circuit die. This leads to considerable difficulty in testing such two-die integrated circuit packages.
There is therefore a need for an integrated circuit package which lends itself more readily to testing.
The present invention is directed towards providing such an integrated circuit package, and the invention is also directed towards a method for producing an integrated circuit package having two dies with input and output terminals of integrated circuits of the dies being directly addressable for testing of the integrated circuit package.